[PATCH] i386: Get ebp from unwinder state when continuing fallback backtrace
[pandora-kernel.git] / include / asm-i386 / unwind.h
1 #ifndef _ASM_I386_UNWIND_H
2 #define _ASM_I386_UNWIND_H
3
4 /*
5  * Copyright (C) 2002-2006 Novell, Inc.
6  *      Jan Beulich <jbeulich@novell.com>
7  * This code is released under version 2 of the GNU GPL.
8  */
9
10 #ifdef CONFIG_STACK_UNWIND
11
12 #include <linux/sched.h>
13 #include <asm/fixmap.h>
14 #include <asm/ptrace.h>
15 #include <asm/uaccess.h>
16
17 struct unwind_frame_info
18 {
19         struct pt_regs regs;
20         struct task_struct *task;
21 };
22
23 #define UNW_PC(frame)        (frame)->regs.eip
24 #define UNW_SP(frame)        (frame)->regs.esp
25 #ifdef CONFIG_FRAME_POINTER
26 #define UNW_FP(frame)        (frame)->regs.ebp
27 #define FRAME_RETADDR_OFFSET 4
28 #define FRAME_LINK_OFFSET    0
29 #define STACK_BOTTOM(tsk)    STACK_LIMIT((tsk)->thread.esp0)
30 #define STACK_TOP(tsk)       ((tsk)->thread.esp0)
31 #else
32 #define UNW_FP(frame) ((void)(frame), 0)
33 #endif
34 #define STACK_LIMIT(ptr)     (((ptr) - 1) & ~(THREAD_SIZE - 1))
35
36 #define UNW_REGISTER_INFO \
37         PTREGS_INFO(eax), \
38         PTREGS_INFO(ecx), \
39         PTREGS_INFO(edx), \
40         PTREGS_INFO(ebx), \
41         PTREGS_INFO(esp), \
42         PTREGS_INFO(ebp), \
43         PTREGS_INFO(esi), \
44         PTREGS_INFO(edi), \
45         PTREGS_INFO(eip)
46
47 static inline void arch_unw_init_frame_info(struct unwind_frame_info *info,
48                                             /*const*/ struct pt_regs *regs)
49 {
50         if (user_mode_vm(regs))
51                 info->regs = *regs;
52         else {
53                 memcpy(&info->regs, regs, offsetof(struct pt_regs, esp));
54                 info->regs.esp = (unsigned long)&regs->esp;
55                 info->regs.xss = __KERNEL_DS;
56         }
57 }
58
59 static inline void arch_unw_init_blocked(struct unwind_frame_info *info)
60 {
61         memset(&info->regs, 0, sizeof(info->regs));
62         info->regs.eip = info->task->thread.eip;
63         info->regs.xcs = __KERNEL_CS;
64         __get_user(info->regs.ebp, (long *)info->task->thread.esp);
65         info->regs.esp = info->task->thread.esp;
66         info->regs.xss = __KERNEL_DS;
67         info->regs.xds = __USER_DS;
68         info->regs.xes = __USER_DS;
69 }
70
71 extern asmlinkage int arch_unwind_init_running(struct unwind_frame_info *,
72                                                asmlinkage int (*callback)(struct unwind_frame_info *,
73                                                                           void *arg),
74                                                void *arg);
75
76 static inline int arch_unw_user_mode(const struct unwind_frame_info *info)
77 {
78 #if 0 /* This can only work when selector register and EFLAGS saves/restores
79          are properly annotated (and tracked in UNW_REGISTER_INFO). */
80         return user_mode_vm(&info->regs);
81 #else
82         return info->regs.eip < PAGE_OFFSET
83                || (info->regs.eip >= __fix_to_virt(FIX_VDSO)
84                     && info->regs.eip < __fix_to_virt(FIX_VDSO) + PAGE_SIZE)
85                || info->regs.esp < PAGE_OFFSET;
86 #endif
87 }
88
89 #else
90
91 #define UNW_PC(frame) ((void)(frame), 0)
92 #define UNW_SP(frame) ((void)(frame), 0)
93 #define UNW_FP(frame) ((void)(frame), 0)
94
95 static inline int arch_unw_user_mode(const void *info)
96 {
97         return 0;
98 }
99
100 #endif
101
102 #endif /* _ASM_I386_UNWIND_H */